Elasmobranchii is a subclass of Chondrichthyes that includes sharks, rays, and sawfish. These cartilaginous fishes are characterized by their five to seven gill slits located on the sides of the head, a generally flattened body shape (especially in rays and skates), and often possess a pointed snout. They are predominantly marine predators, although some species are bottom-dwellers or filter feeders. Elasmobranchs have a diverse range of feeding strategies and occupy various ecological niches within marine ecosystems.